Hydrofoil watercraft

ABSTRACT

Disclosed is a fuselage assembly (100) configured to be attached to a mast assembly (50) of a powered hydrofoil watercraft (1). The fuselage assembly (100) comprises a mast assembly fixation section (106) and an outer housing portion (170) which accommodates, in particular surrounds or encases, a propulsion device (200), in particular an impeller (201), and which outer housing portion (170) at least partially limits an outer dimension of a flow channel (161) through which water is transported during operation of the hydrofoil watercraft (1). The outer housing portion (170) comprises an attachment portion (310) on which a tail unit (300), in particular 10 comprising a stabilizing member (301) such as a stabilizing wing (302), is formed or attachable thereto. In addition or alternatively, the propulsion device (200) may be accommodated in the outer housing portion (170) such that a user is prevented from touching the propulsion device (200).

FIELD OF THE INVENTION

The present invention relates to a hydrofoil watercraft, in particular to an electrically powered hydrofoil surfboard.

BACKGROUND

Powered surfboards gained increased popularity in recent years. In the field of powered surfboards, surfboards incorporating a hydrofoil for reducing the power required to travel have been developed. Powered surfboards known from the prior art have the problem, that they are difficult to transport and that they are not sufficiently safe for a user.

SUMMARY OF THE INVENTION

There is thus a need for an improved powered hydrofoil watercraft that addresses the above disadvantages.

According to the present disclosure, a fuselage assembly for a powered hydrofoil watercraft according to independent claim 1 is provided. Advantageous further formations are subject of the dependent claims.

In addition, other desirable features and characteristics will become apparent from the summary and detailed description, and the appended claims, taken in conjunction with the accompanying drawings.

Embodiments of the present invention relate to improvements of powered hydrofoil watercrafts, in particular powered hydrofoil surfboards.

According to an embodiment, a fuselage assembly may be provided. The fuselage assembly is configured to be attached to a mast assembly of a powered hydrofoil watercraft, in particular of a hydrofoil watersports gear like a powered hydrofoil surfboard. The fuselage assembly comprises a mast assembly fixation section and an outer housing portion. The outer housing portion accommodates a propulsion device. The outer housing portion may surround or encase the propulsion device. The propulsion device may be a propeller. The propulsion device may be an impeller. According to the present disclosure, an impeller may be understood as a propeller which is enclosed or encased by a ring like housing portion, and which is used in combination with a stator. The outer housing portion may at least partially limit an outer dimension of a flow channel through which water is transported during operation of the hydrofoil watercraft. The flow channel may be configured such that its dimension, in particular its cross sectional area, is reduced towards its outlet side, for example from its inlet opening towards its outlet opening. The flow channel may thus be configured such that its cross sectional area at the outlet is the smallest cross sectional area of the flow channel. For that, the flow channel may be formed tapered towards its outlet. In other words, the flow channel may be configured such that a cross sectional area of the flow channel at the inlet or at another position between the inlet and the outlet is larger than a cross sectional area of the flow channel at the outlet. In some embodiments, the cross sectional area of the flow channel at the outlet is 90% to 80% of the cross sectional area of the flow channel at the inlet or at another position between the inlet and the outlet. In some embodiments, the cross sectional area of the flow channel at the outlet is at least 5% smaller than the cross sectional area of the flow channel at the inleet. According to the present disclosure, the cross sectional area may be the area of the flow channel in a plane extending perpendicular to the longitudinal middle axis of the fuselage assembly.

The outer housing portion may be configured to allow an attachment of a tail unit or may itself be configured to comprise or define a tail unit. The outer housing portion may comprise an attachment portion on which a tail unit may be releasably or fixedly provided. The outer housing portion may be integrally formed with the tail unit. The tail unit may comprise a stabilizing wing, for example a horizontal stabilizing wing and/or a vertical stabilizing wing. Accordingly, elements of a hydrofoil assembly may be realized directly on an outer housing portion of a fuselage assembly. In this way, a drive assembly may be integrated into a hydrofoil assembly so that a compact and integrated construction is achieved that for example reduces the number of parts of a powered hydrofoil watercraft.

In addition or alternatively to the provision of the tail unit on the outer housing portion, the outer housing portion may be configured to allow that the propulsion device is accommodated in the outer housing portion such that a user is prevented from touching the propulsion device. In this way, the safety of the fuselage assembly and, thus, of a powered hydrofoil watercraft comprising such a fuselage assembly can be increased.

In some embodiments, the outer housing portion may be configured for detachably fixing the tail unit. The detachable fixation may be achieved by means of positive locking. For example, the detachable fixation may be realized by means of screwing or a quick release lock. For example, the detachable fixation may be realized by means of a plug and socket connection. The detachable fixation may be achieved by means of a dovetail geometry or by means of pins. For that, the outer housing portion may comprise suitably formed sections that allow a corresponding fixation of the tail unit. The housing portion may comprise an attachment flange. The attachment flange may comprise a threaded opening for receiving threaded fasteners.

In some embodiments, the tail unit or elements of the tail unit may be integrally formed with the outer housing portion. For example, the tail unit or at least one stabilizing wing thereof may be integrally formed with the outer housing portion, for example by way of casting or injection molding or by way of additive manufacturing.

In some embodiments, the fuselage assembly further comprises a wing attachment section and a front wing attached to the wing attachment section, wherein the wing attachment section may be provided at a front portion of the fuselage assembly and may be configured to detachably mount the front wing. The wing attachment section may comprise threaded openings allowing to fix the wing by means of threaded fasteners such as screws.

In some embodiments, the tail unit is transferable between a use state and a stowing state. The use state may be a state in which the tail unit is arranged to normally exert its predetermined function, for example to provide or add stability during movement of the powered hydrofoil watercraft. The tail unit may comprise different configurations depending on the effect that is to be achieved. For example, the tail unit may comprise at least one stabilizing wing. For example, the tail unit may comprise a horizontal stabilizing wing mainly extending in horizontal direction during use and/or may comprise a vertical stabilizing wing mainly extending in vertical direction during use. The outer housing portion may be arranged rotatable about a middle longitudinal axis of the fuselage assembly. Thus, by rotating the outer housing portion, the tail unit may be rotated between the above-mentioned states. The stabilizing wing may be mounted on the outer housing in a cantilevered manner. In other words, at least one stabilizing wing may be coupled to the outer housing only at one end portion of the stabilizing wing so that the stabilizing wing protrudes from the outer housing. In an embodiment, three stabilizing wings may be provided. In a configuration, one of the stabilizing wings may be arranged such that its main extension direction is substantially vertical, in particular extends in parallel to the main mast assembly extension direction and towards a board assembly.

Furthermore, two stabilizing wings may extend from the outer housing at an angle with respect to the vertical stabilizing wing, for example at an angle of 120 degrees. In some embodiments, a stabilizing wing may be configured to protrude from both lateral sides of the outer housing when it is mounted thereto. The stabilizing wing may be coupled to the outer housing at a middle section so that two sections of the same protrude from opposite sides of the outer housing. The stabilizing wing may thus be formed similar to a tangent plane or surface contacting the outer housing at a predetermined portion, for example at a lowermost portion. In some embodiments, the stabilizing wings may be pivotably arranged on the outer housing. A stabilizing wing mounted to the outer housing at a middle section thereof may be releasably coupled to the housing rotatable about an axis substantially perpendicular to the outer periphery of the outer housing at the coupling section.

In some embodiments, the fuselage assembly may further comprise a front wing configured and arranged to generate a lifting force during movement of the front wing in water. The front wing may be coupled to a front portion of the fuselage assembly. The fuselage assembly may comprise a wing attachment section for fixing the front wing on the fuselage assembly. In some embodiments, the front wing may be transferable between a use state and a stowing state. The use state may be a state in which the front wing is arranged to normally exert its predetermined function, for example to generate a lifting force. The front wing may comprise different configurations depending on the effect that is to be achieved. For example, the front wing may be designed such that a high lifting force is generated at low travelling speeds. In the use position, the front wing may be arranged to extend cross to the main extension direction of the mast assembly. The wing attachment section may be rotatable so that the front wing may be rotated by rotating the wing attachment section on the fuselage assembly. In an alternative configuration in which the fuselage assembly comprises a front wing and a tail unit, the fuselage assembly may be coupled to the mast assembly such that it is rotatable as a whole. In this way, the tail unit and the front wing may be simultaneously transferred between the stowing state and the use state by rotating the fuselage assembly.

In some embodiments, the stowing state of the front wing or the tail unit may be achieved by an arrangement according to which the front wing and/or a stabilizing wing of the tail unit are configured foldable. In other words, the wings or at least a portion of the wings may be held on the fuselage assembly by means of pivot assembly allowing to pivot at least a portion of the wing. For example, the wings may be configured such that all of the wings or at least portions thereof may be folded such that they extend from one side of the fuselage assembly, for example a side of the fuselage assembly on which the coupling portion for coupling a mast assembly is provided.

In some embodiments a mast assembly profile and a profile of at least a portion or element of the tail unit and/or of the front wing are arranged substantially in one plane when the tail unit and/or the front wing are in the stowing state. The tail unit and/or the front wing may be rotatable about a longitudinal middle axis of the fuselage assembly or a rotation axis parallel to the longitudinal middle axis of the fuselage assembly, for example such that the tail unit and/or the front wing are at least rotatable about 90° between the use state and the stowing state. In some embodiments, the front wing may alternatively be rotatable about an axis which is perpendicular or skew with respect to the longitudinal middle axis.

A fuselage assembly comprising a front wing as described before and optionally a tail unit as described before may also be referred to as hydrofoil assembly. A fuselage assembly as described before which does not comprise a front wing or other means for generating a lifting force but comprises a propulsion device may also be referred to as driving assembly. A fuselage assembly which comprises a propulsion device as well as a front wing and a tail unit may also be referred to as hydrofoil propulsion unit.

In some embodiments, the outer housing portion comprises an upstream end portion at least partially defining an inlet opening and a downstream end portion defining an outlet portion, for example a nozzle portion with an outlet opening. The nozzle portion may be detachably mounted to the housing portion. The nozzle portion may be made from plastics material, for example from a fiber reinforced plastics material. Alternatively, the nozzle portion may be made from aluminum.

In some embodiments, the housing portion and the propulsion device are configured and arranged with respect to each other such that it is not possible for a user to touch the propulsion device with a human extremity. A length of the outer housing portion and/or the size of the inlet opening and/or the size of the outlet opening and/or the position of the propulsion device in the outer housing portion can be configured such that the propulsion device cannot be touched by a user, for example through the inlet opening and/or the outlet opening. According to an embodiment, in addition or alternatively to the above measures and characteristics a safety member for blocking an access to the propulsion device is provided. The safety member may be provided upstream and/or downstream of the propulsion device. The safety member may be a grid. The safety member downstream of the propulsion device may be a stator. The safety member may be arranged in the flow channel. In addition or alternatively a length of the flow channel between the inlet opening and the propulsion device may be at least 30 mm and/or between 60 mm and 120 mm, for example 80 mm. In addition or alternatively a height or width of the inlet opening may be equal to or smaller than 30 mm, for example 15 mm to 20 mm. In addition or alternatively a length of the stator in flow direction of the flow channel may be equal to or larger than 5 mm and may be for example in a range from 10 mm to 30 mm. In addition or alternatively the size of the outlet opening may be equal to or smaller than 30 mm, for example in a range from 15 mm to 25 mm.

In some embodiments, the flow channel is formed between the outer housing portion and an inner housing portion which is suitable for supporting the propulsion device. In some embodiments, the flow channel may in addition or alternatively formed as a ring channel extending about the longitudinal middle axis and circumferentially surrounding the inner housing portion. A cross section of the ring channel in a direction perpendicular to the longitudinal middle axis may define a ring. In addition or alternatively, the inlet opening is formed between the upstream end portion and an outer surface section of the inner housing portion. In addition or alternatively, the inlet opening is formed as an annular inlet opening or an elliptical inlet opening. In addition or alternatively, the flow channel is configured such that an inlet angle smaller than is realized at the inlet opening. According to the present disclosure, the inlet angle is defined as an angle between an imagined tangent plane contacting the inner housing portion at the inlet opening and the longitudinal middle axis.

In some embodiments, the outer housing portion, in particular the upstream end portion, is connected to the inner housing portion via circumferentially distributed struts arranged around the longitudinal middle axis so that the outer housing portion is held cantilevered on the inner housing portion. The struts may at least partially extend in the longitudinal direction of the fuselage assembly and/or may bridge the inlet opening. The struts may be aerodynamically formed so as to reduce turbulences and may comprise a wing shape.

In some embodiments, at least a portion of the outer housing portion, for example a propulsion device accommodating section, and the rear end portion of the inner housing portion are integrally formed, for example by means of casting or additive manufacturing, thereby defining a propulsion section of the fuselage assembly. In addition or alternatively, the propulsion section is detachably coupled to a front portion of the fuselage assembly.

In some embodiments, the fuselage assembly further comprises a flap mechanism for selectively opening and closing the inlet opening. The flap mechanism may be designed such that a negative pressure generated by the propulsion device automatically actuates the flap mechanism. The flap mechanism may comprise one or more flaps that are pre-biased in the closing direction, and which flaps are moved into an opened position against a pre-biasing force when there is a corresponding negative pressure and are automatically moved into a closed position driven by the pre-biasing force when there is no sufficiently large negative pressure. The flaps may be arranged pivotably and may be pre-biased by means of a spring.

In some embodiments, the fuselage assembly further comprises a front portion adapted to sealingly receive an electric motor. The electric motor may be thermally coupled to a casing of the front portion for cooling purposes. Optionally, a motor housing of the electric motor may also form a part of the casing of the front portion, for example in such a manner that the motor housing gets in contact with water on its outer side, such that a direct cooling of the electric motor is possible. In some embodiments, the motor may be pressed into the front portion. The motor may be integrally formed with the front portion of the fuselage assembly. In particular, the motor may be pressed into the front portion without own housing. In such a configuration, the front portion may form the housing of the motor. In this way, the cooling of the motor can be enhanced. In some embodiments, the motor may be bonded into the front portion which may lead to a noise reduction. In some embodiments, the motor may be bonded or glued into the front portion by means of a thermal conductive paste. In this way, cooling can be enhanced and noise can be reduced. In some embodiments, a bearing plate or end cap of the motor may be watertightly sealed and/or cables connected to the motor may be watertightly sealed. In some embodiments, electric members in the arrangement such as cables, controllers, a power supply and the motor may be directly watertighly sealed so that the components in which they are accommodated do not have to be watertightly sealed. In this way, a configuration may be achieved in which for example the front portion of the fuselage assembly does not need to be watertight. In this way, the sealing effort is reduced.

In some embodiments, the front portion is further adapted to receive a controller couplable to the electric motor, the controller being thermally coupled to the casing of the front portion for cooling purposes. The front portion may optionally comprise a controller receiving space separated and sealed from an electric motor receiving space.

In some embodiments, the mast assembly fixation section may be provided on a top side of the fuselage assembly. In addition or alternatively, the mast assembly fixation section may comprise a mounting recess in which a fuselage assembly fixation portion of the mast assembly can be inserted and locked. The mast assembly fixation section can be designed for a positive locking or an integral connection of the mast assembly with the mast assembly fixation section.

An integrated propulsion unit for a powered hydrofoil watercraft may be provided, comprising a fuselage assembly as described before, an electric motor provided in the fuselage assembly and a propulsion device provided within the outer housing portion. The electric motor is operatively connected to the propulsion device, for example by means of a drive shaft accommodated in the inner housing portion. The drive shaft may be the output shaft of the motor so that the propulsion device may be directly coupled to the motor. Alternatively, the drive shaft may be a shaft within a driveline, for example a shaft which is coupled to the output shaft of the motor via a transmission or via a coupling. The fuselage assembly may comprise a torpedo like appearance, in particular when a front wing and a tail unit are not provided.

Furthermore, a hydrofoil watercraft is provided, in particular a hydrofoil watersports gear which may also be referred to as powered hydrofoil surfboard. The hydrofoil watercraft comprises a board assembly, a mast assembly coupled to a lower portion of the board assembly, and an integrated propulsion unit as described above. A front wing and a tail unit are attached to the fuselage assembly of the integrated propulsion unit.

In some embodiments, the board assembly may comprise a hull which is designed to float on water. In other words, the hull may comprise a lower portion which is specifically designed to provide enhanced floatation characteristics and may comprise an upper portion which is designed and configured to support a user. The upper portion may comprise a support surface which allows a user to lie prone, sit, kneel or stand on the board assembly when riding the hydrofoil watercraft. The upper portion may further comprise an access panel which is removable for gaining access to an interior space of the board assembly. The access panel may be coupled to the hull in a watertight manner so as to seal the interior space against intrusion of water. In this manner, the interior space is qualified for accommodating electrical components such as an accumulator or a control unit for example. The accumulator may be removably mountable in the hull so that the accumulator may be inserted into and removed from the hull through an access opening covered by the access panel.

The board assembly may comprise a control unit. The control unit may be coupled to a power source, for example an accumulator. The accumulator may be detachably received in an interior space of the board assembly and may be detachable for charging purposes. The board assembly may comprise a first receiving unit. The first receiving unit may be coupled to the control unit. The first receiving unit may be configured to wirelessly receive a control signal from a wireless remote control. The remote control may be a handheld remote control holdable by a user and operable by the user to control the hydrofoil watercraft, for example to accelerate and decelerate the same. The board assembly may comprise a second receiving unit. The second receiving unit may be coupled to the control unit. The second receiving unit may be configured to wirelessly receive a control signal from the remote control. Accordingly, a configuration may be provided in which two or more receiving units are provided. Each receiving unit may be configured to receive a signal from the remote control. The control unit may be configured to receive the control signal from the remote control via at least one of the receiving units, for example via the receiving unit at which the signal strength is highest. In an exemplary configuration, the receiving units may be arranged at a distance from each other. For example, the receiving units may be provided in the board assembly at different longitudinal positions and/or laterally offset, for example on opposite sides of a middle longitudinal extension of the board assembly. The first receiving unit may be provided in a front portion, for example in a front end portion, of the board assembly and the second receiving unit may be provided in a rear portion, for example a rear end portion, of the board assembly. In this way, a configuration may be achieved in which it is less likely that a control signal may not be received by the control unit due to a blocked or covered receiving unit. Accordingly, a continuous signal transmission from the remote control to the control unit is achieved. This may be beneficial for situations in which the board assembly is partially under water since water may have a negative effect on signal transmission. During riding the hydrofoil watercraft, situations may occur in which the front portion of the board assembly dives into water whereas the rear portion of the board assembly is out of water at the same time or vice versa. In such a situation, signal transmission from the remote control to the control unit which is not under water is securely possible. Accordingly, providing two or more receiving units and distributing them on the board assembly such that they are arranged at a distance from each other and/or at different edge portions of the board assembly secures the signal transmission even in situations in which portions of the board assembly are under water.

The board assembly may comprise a humidity sensor. The humidity sensor may be provided in the above mentioned interior space of the board assembly in which electronic components such as the accumulator and/or the control unit are arranged. In addition or alternatively, a humidity sensor may be provided in the fuselage assembly in a compartment in which the electric motor or an optional controller for the electric motor are provided. Each humidity sensor may be configured to measure the humidity in compartments in which electric components are accommodated. Each humidity sensor may be coupled to a controller, for example to the controller. Based on a signal received from a humidity sensor, the controller may perform predefined safety routines and/or may output signals reflecting the detected humidity. The signals may indicate to a user that measures for lowering the humidity should be taken. For example, the controller may be configured to output a warning signal to a user, for example to the remote control, when a predetermined humidity threshold value is exceeded. In addition or alternatively, the controller may be configured to cut off electric components from the power supply if a predetermined threshold humidity value is exceeded. Accordingly, the safety of the hydrofoil watercraft may be increased by monitoring one or more electric components regarding humidity in their surroundings.

In addition or alternatively to the above features, the control unit may be configured to provide an energy efficient driving mode. The driving mode may comprise a gliding mode in which the impeller is actively rotated at a speed which allows a fluid to pass the impeller substantially without being applied with a force from the impeller. According to a further configuration, the impeller may be disconnected from the electric motor such that it may be rotated only by means of fluid passing the impeller.

In addition or alternatively, the electric motor may comprise a motor/generator and the control unit may be configured to provide a recovery mode. In the recovery mode, the impeller is actively rotated by fluid passing the same and the rotational force generated is transferred into electric power by the motor/generator which may then by stored in the accumulator. The gliding mode and the recovery mode may be activated in suitable situations, for example a situation in which a user rides a wave and does not need an active motor drive. The recovery mode may also be used during deceleration of the hydrofoil watercraft. According to a configuration, the recovery mode is preset to be normally active so that as much energy as possible is recuperated. The recovery mode may be automatically or manually activated or deactivated depending on the charging level of the accumulator. The recovery mode may be automatically activated if a charging level of the accumulator falls below a predetermined threshold charging level.

In addition or alternatively to one or more of the above-mentioned features of the hydrofoil watercraft, the hydrofoil watercraft may comprise active stabilization and/or auto drive functions. The hydrofoil watercraft may comprise a measurement device, for example an inertial measurement unit. The measurement device may be configured to detect an angular rate and/or orientation and/or acceleration of the hydrofoil watercraft. The measurement device may be accommodated in the board assembly. The measurement device may be used for controlling the motor. The measurement device may be coupled to a control unit as described before. An output signal of the measurement device may be received by the control unit. The control unit may control the motor based on the received input signal. In particular, the motor may be controlled such that the thrust generated by the same is increased or decreased depending on the output signal of the measurement device. In this way, it is possible to control the motor depending on the orientation and/or angular rate and/or acceleration and/or the load distribution on the board assembly. Using a measurement device as described before for controlling the motor or motor controller or control unit allows to implement assistive driving modes. For example, a driving mode may be implemented in which minor uncertainties of a user are compensated by adapting the thrust to the situation. Furthermore, motor may be controlled such that the board assembly is held substantially at the same height above the water surface. In order to control the height of the board assembly above the water surface, the board assembly may comprise a distance sensor allowing to determine the distance between the board assembly and the water surface. In this way, the distance between board assembly and the water surface may be continuously monitored. The control unit may be configured to drive the motor such that a predetermined flight level, i.e. distance between the board assembly and the water surface. The predetermined distance or flight level may be preset by a user, for example by means of an external device such as a remote control or mobile device. The time the board assembly is moved without contacting the water surface, also referred to as flight time, may be determined, for example by monitoring the distance between the board assembly and the water surface and/or by determining the same from power and speed of the hydrofoil watercraft. The flight time may be presented to a user, for example via a display provided on the board assembly, a mobile device or the remote control.

Using the above measurement device and controlling the motor on the basis of its output allows to control the horizontal position and/or the stability of the hydrofoil watercraft. Using such a control-based stabilization has the advantage that stabilizing elements on the tail unit, such as tail wings, may be smaller. In other words, the electronic control of the motor in the above manner may compensate for smaller dimensioned stabilizing features on the tail unit, such as smaller wings. This leads to a smaller and more compact dimension of the tail unit and reduces drag.

According to a further aspect, the nozzle section of the fuselage assembly may be adjustable. For example, the outlet opening of the nozzle section may be adjustable in that its dimension may be changed, for example the dimension of the cross sectional area of the outlet opening. By changing the outlet opening dimension, in particular the diameter, it is possible to more efficiently generate a thrust needed for propulsion of the hydrofoil watercraft at different speeds. The nozzle section may comprise an outlet opening varying device for changing the dimension, for example the diameter of the outlet opening. The outlet opening varying device may comprise length adjustable flexible elongate members for generating a varying force on the edge portion defining the outlet opening. The length adjustable flexible elongate members may comprise heat deformable wires contracting upon application of heat and/or may comprise a tube which contracts upon application of pressure. The flexible elongate members may be woven to a meshwork and applied on or integrated in the nozzle section. The flexible elongate members may form a structure which may also be referred to as pneumatic or hydraulic muscle. In addition or alternatively to the adjustable nozzle section as mentioned before, the fuselage assembly, more precisely the impeller, may comprise adjustable blades, for example with adjustable inclination. Thus, the fuselage assembly may comprise an impeller blade adjusting mechanism for changing the inclination of the impeller blades. Also here, length adjustable flexible elongate members may be integrated into the impeller to allow impeller blade adjustments by deformation. In this way, the use of corrodible bearings can be avoided. According to a further aspect, the nozzle section may be configured interchangeable so that a user may attach differently shaped nozzle sections to the fuselage assembly. In this way, the user can adapt the fuselage assembly to his needs, in particular to his riding style.

According to a further aspect, the impeller may be coupled to the electric motor by means of a free-wheel clutch. Accordingly, a free-wheel clutch may be provided in the force transmission path between the electric motor and the impeller. The free-wheel clutch is arranged such that the impeller may be rotated by water flowing through the same if the electric motor is not active and does not actively rotate the impeller. In this way, a flow resistance of the impeller may be reduced. The free-wheel clutch may be provided at a connection portion at which the impeller is mounted on a drive shaft. Alternatively, the free-wheel clutch may also be provided for coupling drive shaft segments to each other. According to a further aspect, the impeller may be held non-rotatable, or its rotation may be actively blocked or prevented by means of a suitable mechanism, when the electric motor is not operated. The extent to which a rotation of the impeller is allowed may also be controllable depending on the speed of fluid flowing through the impeller. The speed of the fluid may be detected by a suitable means and the rotation speed of the impeller may be adapted to an optimum speed for the current flow speed of the fluid so as to reduce drag.

According to a further aspect, the fuselage assembly may comprise a manipulating device for manipulating the direction of the thrust generated in the propulsion section. In this way, a movement of the hydrofoil watercraft may be controlled or at least assisted. Accordingly, a thrust vectoring nozzle section may be provided. The thrust vectoring nozzle may be a two-dimensional thrust vectoring nozzle or may be a three-dimensional thrust vectoring nozzle. Accordingly, a thrust may be deflected in one plane only (referred to as 2D thrust vectoring), for example in left right direction in a horizontal plane, or may be pivoted in all directions (referred to as 3D thrust vectoring) including an up and down direction. The nozzle section may comprise movable flaps for directing the water flowing out of the nozzle section. The flaps may be actuated using adjusting rods coupled thereto. Using such an arrangement allows for assisted steering of the hydrofoil watercraft or even the implementation of an auto-pilot function.

According to a further aspect, the hydrofoil watercraft can be configured to transmit signals and/or energy at least partially wirelessly between components. For example, signals and/or energy which need to be transferred from components in the board assembly to other components in the board assembly or to components in the mast assembly or a mastbox assembly and/or the fuselage assembly may at least partially be transferred wirelessly. In this way, the number of mechanical connections at separating portions of the hydrofoil watercraft can be reduced. For example, the mast assembly can be configured dismountable from the board assembly for stowing purposes. Usual mast assemblies may comprise cables and/or interfaces that need to be physically coupled to corresponding portions on the board assembly. Hence, it is necessary to provide a watertight connection between mast assembly and board assembly. Thus, it can be beneficial to provide a wireless signal and/or energy transmission arrangement between mast assembly and board assembly. In order to provide wireless signal transmission, one or more transceivers may be arranged in the board assembly and coupled to respective components. For example, a transceiver may be coupled to the control unit. A further transceiver may be provided in the mast assembly or in the fuselage assembly and may be coupled to the electric motor or a motor controller provided in the fuselage assembly. The transceiver in the board assembly may be configured to send and receive signals from the transceiver provided in the mast assembly or the fuselage assembly. In addition or alternatively, wireless power transfer between the board assembly and the mast assembly may be provided. For example, a near field wireless power transmission may be provided between mast assembly and board assembly, for example by means of inductive coupling. A power transmitter, for example a power emitting coil, may be arranged on the board assembly near a position at which the mast assembly is mountable on the board assembly. A receiver, for example a power receiving coil, can be provided in the end portion of the mast assembly which is to be mounted on the board assembly. In this way, power transfer from the board assembly to the mast assembly is possible. In addition or alternatively, a connection between the control unit and the battery may be provided wirelessly. It is beneficial to reduce the number of plug-in connections as far as possible. Wirelessly coupling signal or energy transferring portions greatly increases the user friendliness of the hydrofoil watercraft as there is less need for a user to connect plug connections.

According to a further aspect, the hydrofoil watercraft may comprise an improved cooling arrangement for cooling heat generating components, for example including but not limited to the control unit, motor controller and/or accumulator. The cooling arrangement may be a passive cooling arrangement. The cooling arrangement may be configured as water cooling arrangement, in particular as a cooling arrangement through which water is supplied by means of dynamic pressure of water generated during movement of the hydrofoil watercraft. In this way, it is not necessary to provide a pump for actively pumping cooling water through the assembly. The cooling arrangement may comprise a piping system fluid connected to an inlet opening and an outlet opening and allowing water to enter the piping system through the inlet opening and to exit the piping system through the outlet opening. The piping system may be coupled to or may comprise a heat exchanger or heat transfer member thermally coupled to one or more heat generating components. A first inlet opening may be provided on the fuselage or mast assembly. In addition or alternatively, the board assembly may comprise a second inlet opening on a lower portion thereof. Water may flow through the piping system from the one or more inlet openings to the outlet opening thereby passing the heat exchanger thereby receiving heat.

The control unit may be configured to receive and process various information from one or more sensors provided in the hydrofoil watercraft. The hydrofoil watercraft may comprise a configuration which allows the determination and/or prediction of a necessity for maintenance of certain components. For that, the hydrofoil watercraft may comprise a maintenance determination unit. The maintenance determination unit is configured to receive information from one or more sensors and to processes the received information regarding wear and/or maintenance. The maintenance determination unit may be provided within the hydrofoil watercraft. Alternatively or in addition, the maintenance determination unit may be provided outside the hydrofoil watercraft and may receive data from the hydrofoil watercraft.

The hydrofoil watercraft may be configured to provide maintenance data and/or maintenance information. According to the present disclosure, “maintenance data” shall mean any data allowing the determination of information which is relevant for maintenance of specific parts or assemblies. Maintenance data may comprise an unprocessed signal, for example received from a vibration sensor. The term “maintenance information” is to be understood as maintenance data which was at least partially processed to determine information indicating the necessity of maintenance for a specific part or assembly. Maintenance information may comprise information regarding the predicted remaining lifetime of components and/or assemblies. Maintenance data may be processed in the hydrofoil watercraft, for example in the control unit. Maintenance data may also be read out by means of a suitable device which is not an integral part of the hydrofoil watercraft, for example a mobile device, remote controller or computer. Information transmission may be realized by an interface, for example a wireless interface using known wireless transmission standards.

Maintenance information may be determined based on irregularities in the drive by means of considering the relation between thrust, input power, speed and temperature. The parameters thrust, input power, speed and temperature form maintenance data and may be received from corresponding detecting devices. For example, if there isn't sufficient thrust in reaction to a predetermined amount of input energy, a malfunction is detected. In the drive unit, malfunction or wear and tear may be detected at an early stage and the user may be informed correspondingly. This may prevent damages due to a total failure of certain components and, therefore, increases the safety of the hydrofoil watercraft. Such a configuration also may provide a detection whether the impeller is damaged, the jet drive is clogged or dirty. Relevant data or information which may in addition or alternatively be used are loading cycles of the battery and battery cell aging (for example determined based on temperature measurement). In the control unit, the number of switching cycles may be used to determine the remaining service life of a transistor, for example a MOSFET. Furthermore, the bearing of the motor and sealings may be monitored. The speed of revolution, load and medium in which the hydrofoil watercraft is operated may also be taken into account. The hydrofoil watercraft may also be configured to detect sound generated by the drive and to determine malfunction in case the sound deviates from normal sound. For example, the sound level may be monitored, and a malfunction may be determined if the sound level exceeds a predetermined threshold value.

The hydrofoil watercraft may be configured such that the thrust generated in the propulsion section may be reversed. In other words, the thrust direction may be inverted. The propulsion section may be configured such that the propulsion direction is reversed. For example, the rotation direction of the propulsion device, for example of an impeller, may be inverted. For example, the control unit may be configured to drive the electric motor in opposite direction. In this way, a reverse thrust may be generated. With such a configuration, it is possible to drive the hydrofoil watercraft forwards and backwards. This has the benefit that the maneuverability of the hydrofoil watercraft is increased. A rider may move the board in forward direction or in backward direction. In a situation, in which the rider falls off of the hydrofoil watercraft at high speed, it may take some time before the hydrofoil fully stops. In other words, there may be a considerable distance between the user and the hydrofoil watercraft. In order to reduce the distance, the user may use the remote controller to move the hydrofoil watercraft in backward direction so that a swimming distance for the user may be reduced. Furthermore, reversing the flow direction of fluid may be used to at least partially remove residues clogging the inlet opening. A cleaning mode may be implemented by which a reversed thrust is generated for a predetermined time if clogging of the inlet is detected. In order not to excessively move the board backwards and to enhance cleaning efficiency, the backward thrust may be generated intermitted in a pulsing like manner.

According to a further aspect, the control unit may be configured to detect potential overheating of the electric motor and/or battery. The detection may be based on direct temperature measurement or may be based on indirect temperature determination, for example by means of calculation and/or computational prediction. The control unit may be configured to reduce input power to the electric motor if a predetermined temperature threshold value is exceeded, in particular of one of the electric motor, the control unit and/or the battery. In this way, overheating of one of the components may be prevented. Prior to reducing input power, the control unit may output a warning signal such that a user is informed of the upcoming reduction of power and the corresponding thrust decrease. The control unit may further be configured to limit the power depending on a charging state of the battery or driving mode, for example for increasing the remaining range. The control unit may further be configured to output a signal to a user suggesting to return to base if a distance to the starting point matches with the remaining range based on the battery level.

According to a further aspect, the control unit may be configured to adapt to the driving of a user. For example the control unit may be configured to learn the type of user, for example cautious or aggressive. For that, the control unit may process data using machine learning, in particular using a neural network. The control unit may in this way adapt itself to a user. For example, the control unit may control the electric motor dependent on the user.

The hydrofoil watercraft may be configured to provide information regarding efficiency of a user's driving. The efficiency may be indicated to the user, for example via an indicating means, for example a display, in the remote controller and/or in the board assembly. In this way, the user may optimize his riding style for extending the range of the hydrofoil watercraft. The information regarding efficiency may be combined with position data to determine a point of return for safely reaching the starting position of a ride or for reaching a position at which a battery charging station is available.

According to a further aspect, the hydrofoil watercraft may comprise an emergency mode in which the battery may be over-discharged for providing additional power in emergency situations. The control unit may be configured to bypass an included deep discharge protection circuit or to deactivate a disconnection switch in a deep discharge protection circuit upon a specific emergency command issued by a user, for example by pushing an emergency button on the remote control or on the board assembly.

According to an aspect, the hydrofoil watercraft may comprise communication means for wirelessly connecting the same to a radio communication network. For that, the hydrofoil watercraft may comprise a transceiver. The hydrofoil watercraft may be configured to send and receive data from the radio communication network. Data may include information of the hydrofoil watercraft such as speed. Furthermore, the hydrofoil watercraft may be configured to send a distress signal via the transceiver. For example, the hydrofoil watercraft may comprise an emergency switch, for example an emergency button, which the user may activate in case of an emergency. In reaction to the operation of the emergency switch, a distress signal is output via the transceiver. The distress signal may include position information, if available from a positioning device provided on the board assembly. The communication means may be configured to receive a SIM card. The distress signal may be in the form of an automatically generated emergency call. The communication means may also be used to receive information for navigation purposes, including maps or suggested tours.

According to a further aspect, the hydrofoil watercraft comprising one or more features as described herein is controllable by a remote control. The remote control may be configured as already described in this disclosure and can in addition or alternatively comprise a means for receiving and/or sending information. The information may comprise audio and/or visual information, for example speech or images or videos. The remote control may comprise a communication means for communicating with other watercraft users and/or an instructing person such as a teacher. In this way, teachers may communicate with their pupils and send them instructions, for instance. The remote control may in addition or alternatively comprise a walkie talkie mode allowing users to communicate with each other from rider to rider.

According to a further aspect, the remote control may be configured to measure health data of the user. The remote control can comprise a heart rate detection means and/or may comprise a temperature detection means. In addition or alternatively the remote control may comprise a motion sensor. The motion sensor may detect a motion of the user. The detected motion information may be used for controlling the hydrofoil watercraft, for example for acceleration or deceleration and/or steering. The remote control may be couplable to a mobile device, such as a smartphone or smartwatch, to transfer health data. For that, the remote control may comprise a transceiver for wirelessly coupling the remote control to the mobile device.

According to a further aspect, the board assembly of a hydrofoil watercraft as described in the present disclosure may comprise a user detection device. The user detection device may comprise one or more sensor devices. Each sensor device may be configured to detect the presence of a user on the board assembly, at least in a specific area on the board assembly. The sensor device may include pressure sensors or other type of sensors allowing to detect the presence of a user on the board assembly. The user detection device may comprise a sensor pad or sensor foil provided on the board assembly. The user detection device may be coupled to the control unit. The control unit may be configured to stop the motor if it is detected that no user is present on the board assembly. Alternatively to direct detection of a user on the board assembly, the presence of a user on the board assembly may be indirectly determined by considering information regarding power at acceleration, movement information, etc.

According to a further aspect, the hydrofoil watercraft may comprise a position detection unit or an interface for coupling to a mobile device comprising a position detection unit thereto. The position detection unit may comprise one or more GNSS signal receivers. Based on the received information, the position detection unit may determine the position of the hydrofoil watercraft. Instead of determining the position, a position of a mobile device carried by a user may be used and received by the hydrofoil watercraft instead. Position information may be used for different purposes, including for navigation purposes.

According to an aspect, the determined position may be used in various ways. For example, the determined position may be used for triggering specific actions or for limiting specific functions of the hydrofoil watercraft. The control unit may be configured to control the electric motor depending on the determined position and/or based on a map containing information regarding the surrounding area. The map may be stored in a memory of the control unit and may contain information regarding predetermined zones, for example no driving zones or zones with driving restrictions. For example, the map may contain information regarding nature reserves, harbors, near shore shoals, swimming zones etc. The control unit may continuously monitor the position of the hydrofoil watercraft and determine whether the hydrofoil watercraft is in a predetermined zone. If it is determined that the hydrofoil watercraft is moving in a predetermined zone, actions or commands associated with the predetermined zone may be carried out. For example, if the predetermined zone is a low-speed zone, for example a harbor or a swimming zone, the control unit automatically limits the maximum speed of the hydrofoil watercraft. If, for example, the predetermined zone is a no driving zone, the control unit may automatically stop the hydrofoil watercraft. In order to avoid abrupt stopping and/or to prevent a user from entering a no driving zone, the control unit may output a warning signal indicating that a speed reduction or shut off of the hydrofoil watercraft is imminent. Based on the warning signal, a signaling device may be operated. The signaling device may be a device for visually indicating the warning, for example on a remote control or mobile device coupled to the hydrofoil watercraft, such as a smartphone or smartwatch. The signaling device may comprise a signal lighting provided on the board assembly at a position visible by a user during normal operation of the hydrofoil watercraft. The signaling device may in addition or alternatively comprise a loudspeaker for emitting a warning sound. The user of the hydrofoil watercraft may, thus, be warned in case the hydrofoil watercraft approaches predetermined zones. The map may in addition or alternatively comprise information regarding the depth of the surrounding area. The control unit may control the hydrofoil watercraft based on such information to avoid a collision of the hydrofoil watercraft with the ground. The hydrofoil watercraft may comprise a collision prevention unit. The collision prevention unit may comprise a water depth determining device providing a corresponding depth signal which may be used instead of depth information stored in a map. In addition or alternatively, the collision prevention unit may be configured to determine a distance to other objects such as other watercrafts or swimmers, and to provide a corresponding signal. In addition or alternatively, the hydrofoil watercraft may be configured to support one or more cameras or may be provided with one or more cameras, for example at a front end portion and/or a rear end portion of the board assembly. A camera mounted to the hydrofoil watercraft may be used for detecting objects in the surroundings and may, thus, be part of the collision prevention unit. However, the camera does not need to be used in connection with collision prevention but may be used only as recording device. An interface may be provided for wirelessly coupling one or more cameras to the board assembly and/or a remote control. The camera may be activated by operating a corresponding switch, for example a button (including a virtual button on a display), on the board assembly and/or on the remote control. Operating the switch may trigger a recording mode of the camera. The recording mode may include a mode in which recording takes place for a predetermined time, for example 60s. Recording mode may also include a configuration in which the camera may be continuously active such that a predetermined time in the past may be recorded, for example the last 60s. In this way, it is possible to easily capture adventures. In addition or alternatively, an optical distance and/or speed measurement device may be provided. For example, a laser scanner, for example a lidar system, may be provided on the board assembly for object detection and detection of the surroundings.

According to an aspect, the control unit may comprise an auto pilot mode in which the hydrofoil watercraft drives autonomously. One or more optical distance measurement devices and/or cameras may be used to provide signals for autonomously driving the hydrofoil watercraft. Optical detection devices may also be used to determine an extent of waves on the water surface.

According to an aspect, a display may be provided on a front portion of the board assembly. The display may be used to display information for a user, such as information regarding current operational information, for example residual range, battery charge, travel speed, travel height, travelled distance or even navigation information. The display may be wirelessly coupled to installed cameras such that the user may inspect the recording view of the camera on the display. In this way, a user may look straight ahead independent of the orientation of the camera. Camera and/or other data may also be transferred to a remote control. The camera may be operated via the remote control for controlling the hydrofoil watercraft, by means of operating a switch, speech commands and or gesture commands.

According to an aspect, the hydrofoil watercraft may comprise a lighting arrangement. The lighting arrangement may comprise different lighting portions, for example a headlight portion, a taillight portion, and/or sidelight portions. The lighting arrangement may also comprise at least one light strip. A light strip may extend along the edge of the board assembly. A light strip may extend along the mast assembly, for example along a longitudinal extension direction of the mast assembly. A light strip may extend along at least two portions of a front portion, a side portion and a rear portion of the board assembly. A light strip may extend substantially around the entire board assembly. The light strip may be an LED light strip. The lighting arrangement, for example the light strip, may comprise at least two independently configurable lighting portions which may be independently adjusted, for example regarding brightness and/or color. For example, during movement of the hydrofoil watercraft, a headlight portion may emit white light at high brightness. Sidelight portions may be colored green and red, respectively, corresponding to standard lighting on boats and ships. The lighting arrangement may be used as signal light in an emergency situation, for example if a user operates an emergency switch or button as described before. For example, an emergency mode may be provided in which the lighting arrangement flashes. A predetermined flashing pattern may be emitted, for example signalizing SOS in Morse code. A portion of the lighting arrangement may also be used to signalize the status of specific systems. For example, a portion of the lighting arrangement or a separate lighting portion may indicate a status of certain components and systems, including for example one of battery level, GPS signal strength, speed, motor, control unit and/or battery temperature.

According to a further aspect, a hydrofoil watercraft remote control comprising a heated portion for at least partially heating a user's hand. The heated portion may be integrated into a gripping portion of the remote control. The remote control may be configured pistol like and may be used to operate the hydrofoil watercraft in a manner as already described before with respect to other aspects and embodiments. The remote control may comprise an operating section for adjusting the temperature generated by the heating portion. The heating portion may be controlled such that it is automatically deactivated if the level of a remote control battery falls below a predetermined threshold level.

According to a further aspect, the board assembly of a hydrofoil watercraft as described herein may comprise a foot heating arrangement. A supporting surface of the board assembly on which a user stands may comprise one or more heated sections. Each heated section may be integrated into an upper surface of the board assembly. The foot heating arrangement may be operated by way of a remote control for controlling the hydrofoil watercraft, for example a remote control as described in other aspects and embodiments. The remote control may comprise an operating section for adjusting the temperature generated by the foot heating arrangement. The foot heating portion may be controlled such that it is automatically deactivated if the level of a battery of the hydrofoil watercraft falls below a predetermined threshold level. It is noted that heat generated by components within the board assembly, for example of the battery and/or of a control unit, may be at least partially dissipated towards the supporting surface on which the user stands in order to heat the supporting surface to a certain degree. For that, a heat dissipating arrangement may be provided.

According to a further aspect, the board assembly may comprise solar cells for charging the battery of the hydrofoil watercraft.

According to a further aspect, one or more loudspeakers may be provided. As described before, a loudspeaker may be part of a signaling device. However, one or more loudspeakers may be provided independent of a presence of a signaling device and/or may be configured couplable to a mobile device of a user or to a receiving unit integrated in the hydrofoil watercraft. The loudspeaker may be used for emitting sounds such as music and/or instructions from a navigation system. The loudspeaker may be provided in the board assembly, for example on a front portion of the board assembly. The loudspeaker may be configured to emit sound in a direction towards the user, for example towards an area in which the user's head is normally positioned during riding the hydrofoil watercraft. In other words, the loudspeaker may be provided on the board assembly such that its sound emitting range is oriented towards the area where the users head is normally positioned during riding. The loudspeaker may be configured to radiating high frequencies directionally in a narrow spatial angle towards the latter area in order to compensate for losses. The loudspeaker may comprise a main radiation cone oriented towards and covering the latter mentioned area where a user's head is normally positioned. In addition or alternatively, it is possible to provide an audio exciter or panel driver in the board assembly, for example on an inner upper wall of the board assembly. In this way, a portion of a hull of the board assembly may be caused to vibrate by the exciter so that such portion of the board assembly may function as invisible loudspeaker. On the other hand, it is possible to use exciters to amplify the subjective bass sensation of the user through low-frequency vibrations.

According to an aspect, a remote control may be provided which is configured to provide navigation functions. The remote control may comprise the features as already mentioned before with respect to other aspects and embodiments. In addition or alternatively, the remote control may comprise a display. The display may show a map and/or navigation information. Navigation information may be entered (uploaded) into the remote control or a navigation unit in the board assembly wirelessly coupled to the remote control. Information may be received from communities and/or maps services. Information regarding maps and/or navigation may be automatically loaded into the navigation unit and/or remote control. Favorite spots and or routes may be automatically suggested to a user. Furthermore, the user may use information displayed on the remote control for orientation purposes, for example to verify or monitor his position in relation to a desired destination.

Additional features and advantages of the above aspects and embodiments may be gleaned by the person skilled in the art from the following description of exemplary embodiments, which are not to be construed as limiting, however, drawing reference to the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements.

FIG. 1 shows a perspective view of a hydrofoil watercraft according to an embodiment.

FIG. 2 shows a perspective view of an integrated hydrofoil assembly according to an embodiment.

FIG. 3 shows a bottom view of the integrated hydrofoil assembly of FIG. 2 .

FIG. 4 shows a perspective rearview of a rear portion of the integrated hydrofoil assembly according to FIGS. 2 and 3 .

FIG. 5 shows a perspective view of a hull/fuselage of the integrated hydrofoil assembly according to FIGS. 2 to 4 .

FIG. 6 shows a sectional view of the rear portion of the integrated hydrofoil assembly according to an embodiment.

FIG. 7 shows a sectional view of an aerodynamically formed coupling member according to an embodiment.

FIGS. 8 and 9 show a further embodiment of a fuselage assembly.

FIG. 10 shows a hydrofoil watercraft according to a further embodiment.

FIG. 11 shows possible modifications and embodiments of a hydrofoil watercraft according to further aspects.

All figures are only schematic depictions of exemplary embodiments in which, in particular, distances and dimensional correlations are not presented to scale.

DETAILED DESCRIPTION OF EMBODIMENTS

The following detailed description is merely exemplary in nature and is not intended to limit application and uses. Furthermore, there is no intention to be bound by any theory presented in the preceding background or summary or the following detailed description.

FIG. 1 shows a perspective view of a hydrofoil watercraft 1 according to an embodiment. The hydrofoil watercraft 1 comprises a board assembly 10, a mast assembly 50 and a fuselage assembly 100 coupled to the mast assembly 50.

The board assembly 10 comprises a hull 11 which is designed to float on water. For that, the hull 11 comprises a lower portion 12 which is specifically designed to contact water and comprises an upper portion 13 which is configured to support a user. The upper portion may comprise a support surface 14 which allows the user to lie prone, sit, kneel or stand on the board assembly 10 when riding the hydrofoil watercraft 1. In the support surface 14, and access panel 15 is detachably provided. The access panel 15 covers an access opening to an interior space of the board assembly 10. The access panel 15 is coupled to the hull 11 in a watertight manner so as to seal the interior space against an intrusion of water. Although not shown in the drawings, the interior space may accommodate electric components such as a power supply, for example an accumulator. Furthermore, a control unit powered by the accumulator and comprising a wireless receiving unit may be provided. The control unit and/or the power supply may be coupled to the fuselage assembly 100 to supply power and/or control signals to the fuselage assembly, in particular to drive an electric motor arranged in the fuselage assembly 100.

On the lower portion 12 of the hull 11, the mast assembly 50 is fixedly coupled to the board assembly 10. In an embodiment, the mast assembly 50 is detachably fixed to the board assembly 10 in order to allow a space saving stowing of the hydrofoil watercraft 1. For that, the mast assembly 50 may comprise a board assembly fixation portion 51. The board assembly fixation portion 52 is configured to cooperate with a mast assembly coupling portion (not shown) provided on the lower portion 12 of the hull 11. The board assembly fixation portion 52 may comprise a fastening flange which is integrated into the hull 11. The board assembly fixation portion 52 may comprise an insertion portion or protrusion. The mast assembly coupling portion on the board assembly 10 may comprise a mounting recess for receiving the board assembly fixation portion 52. Accordingly, the board assembly fixation portion 52 may be inserted into the mounting recess provided in the lower portion 12 of the hull 11 of the board assembly 10 in order to couple the mast assembly 50 to the board assembly 10. The board assembly fixation portion 52 may be configured to be coupled to the board assembly 10 by means of positive locking. For example, the board assembly fixation portion 52 and the board assembly 10 may be configured to be screwed to each other. For that, the mast assembly coupling portion of the board assembly 10 may comprise a fixation flange which provides a suitable support for fastening devices such as screws.

The mast assembly 50 further comprises a fuselage assembly fixation portion 54. According to an embodiment, the fuselage assembly fixation portion 54 may be configured to cooperate with a mast assembly coupling portion 106 provided on the fuselage assembly 100. The mast assembly coupling portion 106 may comprise a mounting recess 107 and may be configured to accommodate the fuselage assembly fixation portion 54 therein. According to the embodiment, the mounting recess 107 is provided in an upper portion of the fuselage assembly 100 so that according to the embodiment, the fuselage assembly 100 is coupled to one end portion 53 of the mast assembly 50. Accordingly, the fuselage assembly 100 may be coupled to one end portion 53 of the mast assembly 50 and the board assembly 10 may be coupled to the mast assembly 50 at the other opposite end portion 51 of the mast assembly 50. The fuselage assembly 100 is thus coupled to the board assembly 10 by means of the mast assembly 50.

The fuselage assembly 100 according to the exemplary embodiment comprises a front portion 101 and a rear portion 140. The rear portion 140 is detachably coupled to the front portion 101. In some embodiments, the rear portion 140 may be fixedly coupled to the front portion 101 and may in particular be non-detachably coupled to the front portion.

The front portion 101 comprises a front section 102, a middle section 103 and a rear section 104. The front section comprises a wing attachment section 105, the middle section 103 comprises a mast assembly fixation section 106 and the rear section 104 comprises a coupling section 108 for coupling the rear portion 140 to the front portion 101. The front portion 101 may further comprise an accommodating section 109 for internally accommodating further elements such as elements of a drive unit and/or elements of a power supply. The accommodating section 109 may in addition or alternatively be configured to accommodate a portion of the rear portion 140 therein. The front portion 101 may comprise a hull or casing 110. The casing 110 may be formed as a single part and may be aerodynamically formed with a tip end portion at the front section 102. In the middle section 103 and the rear section 104, the casing 110 may be formed tubular, for example hollow cylindrical and/or elliptical. But in general, other shapes and configurations are possible including for example a configuration in which the shape of an outer circumference of the casing differs from the shape of an inner circumference of the casing. For example, the outer circumference may be shaped triangular, in particular with rounded corners, and the inner circumference of the casing may be formed rounded, for example circular.

The wing attachment section 105 may be formed by a recess provided in the front section 102 so that it is possible to at least partially accommodate a wing 112, in particular a front wing, therein. In this way, it may be prevented that the wing 112 fully protrudes from the casing so that the application of such a wing 112 does not considerably enlarge an outer dimension, for example a height dimension of the fuselage assembly, for instance. In the rear section 104, openings 111 may be provided in the casing 110. The openings 111 may be provided for coupling purposes, for example for the insertion and accommodation of fastening members 150 for coupling the rear portion 140 of the fuselage assembly 100 to the front portion 101 of the fuselage assembly 100. Accordingly, as is shown in the Figures, the fuselage assembly may comprise a two-part construction in which the rear portion 140 and the front portion 101 are detachably couplable to each other.

The mast assembly fixation section 106 is configured to couple the mast assembly to the fuselage assembly 100. The mast assembly fixation section 106 may comprise a mounting recess 107 for receiving at least a portion of fuselage assembly fixation portion 54 of the mast assembly 50.

The wing 112 is detachably mountable to the wing attachment section 105 and is configured to generate a lifting force during movement of the hydrofoil watercraft 1 in water. As already indicated before, the wing 112 according to the embodiment may also be referred to as front wing as according to the exemplary embodiment, the wing 112 is provided at the front section 102 of the fuselage assembly 100. The wing 112 may comprise different shapes and sizes depending on the characteristics that are to be achieved. For example, the wing 112 may comprise a shape that generates a high lifting force already at low speeds or may comprise a shape that needs a higher speed for generating a desired lifting force.

The rear portion 140 comprises a coupling section 141 configured to couple the rear portion 140 to the front portion 101. The coupling section 141 comprises a coupling flange 142 adapted to be coupled to the coupling section 108 of the front portion 101 of the fuselage assembly 100. The coupling flange may comprise a cylindrical portion 143 with an outer circumferential surface 144. The outer circumferential surface 144 may be dimensioned according to an inner circumferential surface in the coupling section 108. Both circumferential surfaces may be provided parallel with respect to each other and may be arranged to extend parallel with respect to a longitudinal middle axis A1 of the fuselage assembly 100. In particular, the outer diameter of the outer circumferential surface 144 may correspond to the inner diameter of the inner circumferential surface. Engaging portions 145 for fastening members may be provided in the coupling flange 142, for example equidistantly about the longitudinal middle axis A1. For example, the engaging portions 145 may be threaded openings suitable for receiving threaded fastening members such as screws which may be used for coupling the front portion 101 and the rear portion 140 by inserting them through the openings 111 and screwing them into the threaded openings 145.

The coupling section 141 may further comprise an accommodating section 146 which is configured to be accommodated in the front portion 101 of the fuselage assembly 100. The accommodating section 146 may be formed hollow cylindrical with an accommodating space 147 suitable for receiving an element of a drive train, for example a coupling member for coupling an electric motor to a drive shaft. The accommodating section 146 is arranged on and extends from one side of the coupling flange 142. At a free end of the accommodating section 146, a fixation flange 148 is provided which according to the embodiment, provides an annular fixation surface that may extend about the longitudinal middle axis A1 and in a plane which is perpendicular to the longitudinal middle axis A1. The fixation flange 148 provides a support for a drive member such as an electric motor, in particular in such a manner that the drive member can be mounted on an outer side of the accommodating section 146. For that, the fixation flange 148 may comprise fixation openings 149 arranged on the fixation flange 148. In some embodiments, the accommodating section 146 may be omitted. The electric motor may be arranged in and fixed on the front portion 101 of the fuselage assembly 100 so that there needs to be no fixation option such as the above mentioned fixation flange 148 for mounting the electric motor on the coupling section. For example, the electric motor may be pressed into the front portion 101.

In addition to the above or alternatively, the rear portion 140 may comprise a propulsion section 160. The propulsion section 160 may extend from the above coupling flange 142 on one axial side so that it extends along the longitudinal middle axis A1, for example on the side of the coupling flange which is opposite to the side where the accommodating section 146 is provided.

The propulsion section 160 may define a flow channel 161 for water, in which water may be accelerated to create a propulsive force. The flow channel 161 may be configured ring-like, in particular with an annular or elliptical inlet and such that water flows therethrough as indicated in FIG. 6 by dashed arrows. The propulsion section 160 may comprise an inlet section 162, an intermediate section 163 and an outlet section 164. The inlet section 162 may be designed such that a radial entry of water into the propulsion section 160 is possible. According to the present disclosure, radial entry is to be understood as a direction in which the flow of water is at least partially directed cross or inclined to the longitudinal middle axis A1 of the fuselage assembly 100, at least upon entering the flow channel 161, and, thus, has a directional component in radial direction, more precisely towards the longitudinal middle axis A1. However, it is also possible to provide an inlet section which is designed such that an axial entry of water into the propulsion section is possible. For example, the ring-like flow channel may be configured such that a radial outer wall and/or a radial inner wall extends or extend in parallel with the longitudinal middle axis, at least at the inlet section. Accordingly, water entering such a flow channel flows in parallel to the longitudinal middle axis, at least at the inlet section.

The flow channel 161 may be defined between an outer housing portion 170 and an inner housing portion 180.

The outer housing portion 170 may be defined by a propulsion device accommodating section 171 and a nozzle section 172. The propulsion device accommodating section 171 is configured to accommodate a propulsion device 200, for example to surround or to encase the propulsion device 200. The propulsion device accommodating section 171 may comprise the shape of a hollow rotation body, for example tubular or similar to a hollow cylindrical section with the difference that the inner wall surface and/or the outer surface of the hollow body may at least partially extend inclined with respect to a middle axis and/or may at least partially be curved in longitudinal direction and non-straight.

The inner housing portion 180 may be at least partially arranged coaxially within the outer housing portion 170. Accordingly, the flow channel 161 may be formed between an outer surface section 181 of the inner housing portion 180 and an inner surface section 173 of the outer housing portion 170. According to the embodiment, an inlet opening 178 is defined between an upstream end portion of the outer housing portion 180 and the outer surface section 181 of the inner housing portion 180. In other words, the inner housing portion 180 is arranged such that a portion of the outer housing portion 170 and a portion of the inner housing portion 180 overlap each other in longitudinal direction (x-direction in the drawings) of the fuselage assembly 100 thereby forming a portion of the flow channel 161 between them.

The inner housing portion 180 comprises a front end portion 182 and rear end portion 183. The front end portion 182 is coupled to the coupling flange 142 or integrally formed therewith. An outer circumferential dimension, for example the diameter, of the inner housing portion 180 at the front end portion 182 is larger than the outer circumferential dimension at the rear end portion 183. Accordingly, the outer circumference of the inner housing portion 180 between the front end portion 182 and the rear end portion 183 may be tapered, in particular tapered towards the rear end portion 183. The rear end portion 183 is configured to support the propulsion device 200, for example the impeller 201. The rear end portion 183 may be configured to accommodate a rear bearing 202 for rotatably supporting the propulsion device 200 therein.

The propulsion device 200, in particular the impeller 201, may be operatively connected to a drive device such as an electric motor by means of a drive shaft 203. In an embodiment, the drive shaft 203 may be supported in the rear portion 140 of the fuselage assembly 100 by means of a rear bearing 202 and a front bearing 204 and such that a rear end portion 205 of the drive shaft 203 protrudes from the rear end portion 183. The front bearing 204 may be supported in the coupling flange 142. The rear bearing 202 may be provided in and may be supported by the rear end portion 183. The propulsion device 200 is fixedly and integrally rotatably mounted on the rear end portion 205 of the drive shaft 203.

The outer housing portion 170 may be coupled to the inner housing portion 180 on an upstream side of the outer housing portion 170, in other words, on the inlet side, by means of struts 190. The struts 190 may be equidistantly arranged about the longitudinal middle axis A1. Each strut 190 may be aerodynamically formed, for example as shown in FIG. 7 which shows a cross section of the struts in a direction parallel to the longitudinal middle axis A1. In this way, disturbances of a water flow passing the struts are reduced.

The nozzle section 172 may be detachably mounted to a downstream or rear end portion of the propulsion device accommodating section 171. The nozzle section 172 may comprise or define an outlet opening 191 at a downstream portion thereof. The nozzle section 172 may comprise a stator portion or stator 174 comprising multiple stationary guide vanes. However, in some embodiments, the stator 174 may be arranged in the propulsion device accommodating section 171. In other words, the stator 174 does not have to be provided in the nozzle section 172 but may be provided at other suitable positions in the flow channel 161. It is also possible to provide the stator 174 upstream of the propulsion device. Accordingly, an inverse arrangement may also be realized in which water first flows through the stator and then passes the impeller. In the embodiment, the stator 174 is arranged downstream of the propulsion device 200. The stator portion 173 may be configured such that a user may not pass a finger through the space between guide vanes 175. In other words, the distance between adjacent guide vanes 175 may be such that passing of a portion of the human body therethrough is not possible at all or is only possible to an extent in which the propulsion device 200 may not be reached or touched. Accordingly, the distance between the guide vanes 175 may be set depending on a distance between the stator 174 and the propulsion device 200.

In some embodiments, the fuselage assembly 100 may comprise a tail unit 300. In the embodiment, the tail unit 300 is provided in the rear portion 140 of the fuselage assembly 100. The tail unit 300 may also be referred to as stabilizing portion and according to the embodiment, comprises a stabilizing member 301. According to an example, the stabilizing member 301 comprises a wing 302, more precisely a horizontal wing as is shown in FIG. 2 , for instance. In addition or alternatively, a vertical wing may be provided.

The fuselage assembly 100 may comprise an attachment portion 310 for detachably attaching the stabilizing member 301 thereto. On the other hand, according to a modification, the stabilizing member 301 may be integrally formed in the rear portion 140 of the fuselage assembly 100, for example by casting or injection molding.

In FIGS. 1 to 6 , embodiments are shown in which the rear portion 140 comprises an attachment portion 310 that allows to detachably mount the stabilizing member 301 thereon. In the embodiment, the fuselage assembly 100 comprises two attachment flanges 311 each defining a supporting surface 312. Each attachment portion 310, for example each attachment flange 311, may comprise a threaded opening 313 which is configured to receive a threaded fastener 314 such as a screw. Accordingly, the stabilizing member 301 may be detachably attached by means of screws 314 as shown in FIG. 3 . As is shown in the embodiments, the attachment portion 310 may be provided on the outer housing portion 170, for example in the propulsion device accommodating section 171. For that, the attachment portion 310 may be integrally formed in an outer circumferential portion 176 of the outer housing portion 170.

In some embodiments, the fuselage assembly 100 is configured such that the tail unit 300 is transferable between a use state and a stowing state. The use state may be a state in which the tail unit 300 is arranged to normally exert its predetermined function, for example to provide or add stability during movement of the powered hydrofoil watercraft 1. The tail unit 300 may comprise different configurations depending on the effect that is to be achieved. For example, the tail unit 300 may comprise at least one the above mentioned stabilizing wings 302. For example, the tail unit 300 may comprise a horizontal stabilizing wing mainly extending in horizontal direction during use and/or may comprise a vertical stabilizing wing mainly extending in vertical direction during use. In some embodiments, the stabilizing wing may be curved or may comprise at least two sections angled with respect to each other. The stabilizing wing may comprise a kink or sharp bend. Further configurations are possible. For example, the tail unit may comprise two stabilizing wings forming a V-shape. The tail unit 300 may be arranged rotatable about the longitudinal middle axis A1 of the fuselage assembly 100. The outer housing portion may be arranged rotatable about the longitudinal middle axis A1 of the fuselage assembly 100. Thus, by rotating the outer housing portion, the tail unit may be rotated between the above-mentioned states. The front wing 112 may be attached in a similar manner and may also be rotatable between a stowing state and a use state. The wing attachment section 105 may be rotatable so that the front wing 112 may be rotated by rotating the wing attachment section 105 about the longitudinal middle axis A1. However, as mentioned in the summary, different arrangements are possible including an arrangement in which one of the stabilizing wings and/or the front wing is rotatable about a vertical axis or an axis perpendicular to an outer surface of the portion it is mounted to.

In some embodiments, a mast assembly profile and a profile of the tail unit and/or of the front wing are arranged substantially in one plane when the tail unit and/or the front wing are in the stowing state. The tail unit and/or the front wing may be rotatable about a longitudinal middle axis of the fuselage assembly, for example such that the tail unit and/or the front wing are at least rotatable about 90° between the use state and the stowing state.

In the embodiments as shown, the fuselage assembly 100 is coupled to an end portion 53 of the mast assembly 50 so that the fuselage assembly 100 forms an end portion of the hydrofoil watercraft 1. In other words, according to the embodiment as shown in FIG. 1 , the mast assembly 50 extends between the fuselage assembly 100 and the board assembly 10. It is however, also possible to couple the fuselage assembly 100 at a middle section 55 between the end portions 51, 53 of the mast assembly 50. In this way, the fuselage assembly 100 may be coupled to the mast assembly 50 at a position between end portion 53 and end portion 51. In this way, end portion 53 may be available for the fixation of a further element, such as a generic hydrofoil assembly or a wing.

In the embodiments shown in the figures, the fuselage assembly 100 combines a drive assembly and a hydrofoil assembly. In other words, the drive assembly is integrated into the hydrofoil assembly 100. However, it is also possible to provide a separate generic hydrofoil assembly and a separate drive assembly embodied by a fuselage assembly as described before. For example, a configuration may be provided in which the fuselage assembly that does not comprise elements like front wing and tail unit, is coupled to the mast assembly 50 at a portion between a generic hydrofoil assembly and the board assembly 10.

A modification to the embodiment shown in FIGS. 1 to 7 will be described with reference to FIGS. 8 and 9 . As already mentioned before, the propulsion section 160 may be configured such that the stator 174 is arranged upstream of the propulsion device 200. Furthermore, the propulsion section 160 may be provided at the front portion 101 of the fuselage assembly and the mast assembly fixation section 106 may be arranged in the rear portion 140. In the modification as shown in FIGS. 8 and 9 , the fuselage assembly 100 is embodied as a drive assembly 400 which does not comprise hydrofoil characteristics and only serves a propulsion purpose. A generic separate hydrofoil assembly 500 corresponding to known generic hydrofoil assemblies including a front wing 502 and a tail unit 510 coupled to each other by means of a fuselage 501 is provided at the lower end portion 53 of the mast assembly 50. The tail unit 510 comprises a stabilizing member 511 in the form of a wing 512. The drive assembly 400 is coupled to the mast assembly at a position between end portions 51 and 53 of the mast assembly 50. An inlet opening 401 allows for an inflow of water in axial direction and an outlet opening 402 also allows for an outflow of water in axial direction. Other features are similar to the features as already described before in connection with the embodiment of FIGS. 1 to 7 with the difference that the inlet opening 401 is provided at a foremost portion of the drive device 400/fuselage assembly 100 and the stator 174 is provided upstream of the propulsion device 200. The mast assembly fixation portion 106 is provided at a rearmost portion of the drive device 400. As is also obvious, further components like the electric motor are accommodated in the rear portion 140 of the fuselage assembly 100 for example at a position between the mast assembly fixation portion 106 and the propulsion section 160. The outlet opening 402 is defined ring-like and surrounds the rear portion 140 of the fuselage assembly 100.

A further embodiment of a hydrofoil watercraft 1 is shown in FIG. 10 . The hydrofoil watercraft 1 may comprise one or more of the features as described before and may be a modification of the hydrofoil watercraft 1 as described before. The board assembly 10 may comprise a control unit 16. The control unit 16 may be coupled to a power source, for example an accumulator 20. The accumulator 20 may be detachably received in an interior space of the board assembly 10 and may be detachable for charging purposes. The board assembly 10 may comprise a first receiving unit 17. The first receiving unit 17 may be coupled to control unit 16. The first receiving unit 17 may be configured to wirelessly receive a control signal from a wireless remote control 21. The remote control may be a handheld remote control 21 held by a user and operated by the user to control the hydrofoil watercraft 1, for example to accelerate and decelerate the same. The board assembly 10 may comprise a second receiving unit 18. The second receiving unit 18 may be coupled to the control unit 16. The second receiving unit 18 may be configured to wirelessly receive a control signal from the remote control 21. Accordingly, a configuration may be provided in which two receiving units 17, 18 are provided. Each receiving unit 17, 18 may be a transceiver. Both receiving units 17, 18 may be configured to receive a signal from the remote control 21. The control unit 16 may be configured to receive the control signal from the remote control 21 via the receiving unit 17, 18 at which the signal strength is highest. In an exemplary configuration, the receiving units 17, 18 may be arranged at a distance from each other. For example, the receiving units 17, 18 may be provided in the board assembly at different longitudinal positions and/or laterally offset, for example on opposite sides of a middle longitudinal extension of the board assembly 10. In the embodiment as shown in FIG. 10 , the first receiving unit 17 is provided in a front portion of the board assembly and the second receiving unit 18 is provided in a rear portion of the board assembly. In this way, a configuration may be achieved in which it is less likely that a control signal may not be received by the control unit 16 due to a blocked or covered receiving unit. This may be beneficial in situations in which the board assembly is partially under water since water may have a negative effect on signal transmission. During riding the hydrofoil watercraft, situations may occur in which the front portion of the board assembly 10 dives into water whereas the rear portion of the board assembly stays out of the water or vice versa. In such a situation, signal transmission from the remote control to the control unit 16 may be securely possible via the second wireless receiving unit 18 or the first receiving unit 17, in other words via the receiving unit 17, 18 which is not under water. Accordingly, providing two or more receiving units and distributing them on the board assembly such that they are arranged at a distance from each other secures the signal transmission even in situations in which portions of the board assembly are under water.

The control unit 16 and/or the power supply 20 may be coupled to the fuselage assembly 100 to supply power and/or control signals to the fuselage assembly, in particular to drive an electric motor 205 arranged in the fuselage assembly 100. For that, an electric line 56 may be provided which, for example, couples the control unit 16 to the fuselage assembly.

The board assembly 10 may comprise a humidity sensor 19. The humidity sensor 19 may be provided in the above mentioned interior space of the board assembly 10 in which electronic components such as the accumulator 20 and/or the control unit 16 are arranged. In addition or alternatively, a humidity sensor 206 may be provided in the fuselage assembly 100 in a compartment in which the electric motor 205 or an optional controller 207 for the electric motor 205 are provided. Each humidity sensor may be configured to measure the humidity in compartments in which electric components are accommodated. Each humidity sensor 19, 206 may be coupled to a controller, for example to the controller 16. Based on a signal received from a humidity sensor, the controller may perform predefined safety routines and/or may output signals reflecting the detected humidity. The signals may indicate to a user that measures for lowering the humidity should be taken. For example, the controller may be configured to output a warning signal to a user, for example to the remote control 21, when a predetermined humidity threshold value is exceeded. In addition or alternatively, the controller may be configured to cut off electric components from the power supply if a predetermined threshold humidity value is exceeded. Accordingly, the safety of the hydrofoil watercraft 1 may be increased by monitoring one or more electric components regarding humidity in their surroundings.

In addition or alternatively to the above features, the control unit 16 may be configured to provide an energy efficient driving mode. The driving mode may comprise a gliding mode in which the impeller is actively rotated at a speed which allows a fluid to pass the impeller substantially without being applied with a force from the impeller. According to a further configuration, the impeller may be disconnected from the electric motor such that it may be rotated only by means of fluid passing the impeller. In addition or alternatively, the electric motor 205 may comprise a motor/generator and the control unit may be configured to provide a recovery mode. In the recovery mode, the impeller is actively rotated by fluid passing the same and the rotational force generated is transferred into electric power by the motor/generator which may then by stored in the accumulator. The gliding mode and the recovery mode may be activated in suitable situations, for example a situation in which a user rides a wave and does not need an active motor drive. The recovery mode may also be used during deceleration of the hydrofoil watercraft. According to a configuration, the recovery mode is preset to be normally active so that as much energy as possible is recuperated. The recovery mode may be activated or deactivated depending on the charging level of the accumulator. The recovery mode may be activated if a the charging lever of the accumulator falls below a predetermined threshold charging level.

Further features of different aspects may be gleaned from FIG. 11 . The hydrofoil watercraft 1 may comprise one or more of the features as described before and may be a modification of one of the hydrofoil watercrafts 1 as described before comprising one or more of the features as described below.

In addition or alternatively to one or more of the above-mentioned features of the hydrofoil watercraft, the hydrofoil watercraft may comprise may comprise a measurement device 22, for example an inertial measurement unit. The measurement device 22 may be configured to detect an angular rate and/or orientation and/or acceleration of the hydrofoil watercraft. The measurement device is accommodated in the board assembly 10. The measurement device 22 may be coupled to control unit 16. The measurement device 22 may be used for controlling the motor 205. Different possibilities regarding use of the measurement device 22 and implementations for controlling the motor 205 on the basis of the output of such measurement device 22 are given above and will not be repeated here.

The nozzle section 172 of the fuselage assembly 100 may be adjustable. For example, the outlet opening 191 of the nozzle section 172 may be adjustable in that its dimension may be changed, for example the dimension of the cross sectional area of the outlet opening. By changing the outlet opening dimension, in particular the diameter, it is possible to more efficiently generate a thrust needed for propulsion of the hydrofoil watercraft at different speeds. The nozzle section may comprise an outlet opening varying device 192 for changing the dimension, for example the diameter of the outlet opening 191. The outlet opening varying device may comprise length adjustable flexible elongate members 193 for generating a varying force on the edge portion defining the outlet opening. Details regarding such flexible elongate members 193 were already described and are not repeated here. According to a further aspect, the nozzle section 172 may be configured interchangeable so that a user may attach differently shaped nozzle sections to the fuselage assembly. In this way, the user can adapt the fuselage assembly to his needs, in particular to his riding style.

According to a further aspect, the fuselage assembly 100 may comprise a manipulating device 194 for manipulating the direction of the thrust generated in the propulsion section. In this way, a movement of the hydrofoil watercraft may be controlled or at least assisted. In other words, a thrust vectoring nozzle section 195 may be provided. The nozzle section 195 may comprise movable flaps 196 for directing the water flowing out of the nozzle section.

According to a further aspect, the hydrofoil watercraft may comprise a wireless signal and/or energy transmission arrangement 197, for example between mast assembly and board assembly 10. A transceiver 198 may be arranged in the board assembly 10 and coupled to the control unit 16. A further transceiver 199 may be provided in the mast assembly 50 and may be coupled to the electric motor 205 provided in the fuselage assembly 100. Further details regarding possible signal and or energy transmission arrangements and benefits were already given above and are not repeated here.

According to a further aspect, the hydrofoil watercraft may comprise an improved cooling arrangement 600 for cooling heat generating components, for example including but not limited to the control unit 16, motor controller and/or accumulator. The cooling arrangement 600 may be a passive cooling arrangement. The cooling arrangement 600 may comprise a piping system 601 fluid connected to an inlet opening 602 and an outlet opening 603 and allowing water to enter the piping system through the inlet opening and to exit the piping system through the outlet opening. The piping system 600 may be coupled to or may comprise a heat exchanger 604 or heat transfer member thermally coupled to one or more heat generating components. Possible configurations were already described in the general part of the description.

The hydrofoil watercraft 1 may comprise a maintenance determination unit as described in the general part of this disclosure, which may be integrated into the control unit 16.

According to an aspect, the hydrofoil watercraft may comprise communication means 700 for wirelessly connecting the same to a radio communication network. For that, the hydrofoil watercraft may comprise a transceiver 701.

According to a further aspect, the hydrofoil watercraft comprising one or more features as described herein is controllable by a remote control 21. The remote control may be configured as already described in this disclosure and can in addition or alternatively comprise a means for receiving and/or sending information. According to a further aspect, the remote control may be configured to measure health data of the user. The remote control can comprise a heart rate detection means 23 and/or may comprise a temperature detection means 24. In addition or alternatively the remote control 21 may comprise a motion sensor 25. The motion sensor may detect a motion of the user. The detected motion information may be used for controlling the hydrofoil watercraft, for example for acceleration or deceleration and/or steering.

According to a further aspect, the board assembly of a hydrofoil watercraft as described in the present disclosure may comprise a user detection device 702. The user detection device may comprise one or more sensor devices. Each sensor device may be configured to detect the presence of a user on the board assembly, at least in a specific area on the board assembly.

According to a further aspect, the hydrofoil watercraft may comprise a position detection unit or an interface for coupling to a mobile device comprising a position detection unit thereto. The position detection unit may comprise one or more GNSS signal receivers and may, for example, be integrated into one of the receiving units 17, 18 as described before.

The hydrofoil watercraft may comprise a collision prevention unit. The collision prevention unit may comprise a water depth determining device 703 providing a corresponding depth signal which may be used instead of depth information stored in a map.

According to an aspect, a display 704 may be provided on a front portion of the board assembly 10. The display may be used to display information for a user, such as information regarding current operational information, for example residual range, battery charge, travel speed, travel height, travelled distance or even navigation information.

According to an aspect, the hydrofoil watercraft may comprise a lighting arrangement 705. The lighting arrangement may comprise different lighting portions, for example a headlight portion, a taillight portion, and/or sidelight portions.

According to a further aspect, the hydrofoil watercraft remote control 21 may comprise a heating portion 26 (also referred to as heated portion) for at least partially heating a user's hand. The heated portion may be integrated into a gripping portion of the remote control.

According to a further aspect, the board assembly 10 of a hydrofoil watercraft as described herein may comprise a (foot) heating arrangement or portion 706. A supporting surface of the board assembly on which a user stands may comprise one or more heated sections. Each heated section may be integrated into an upper surface of the board assembly.

According to a further aspect, one or more loudspeakers 707 may be provided. As described before, a loudspeaker 707 may be part of a signaling device. However, one or more loudspeakers may be provided independent of a presence of a signaling device and/or may be configured couplable to a mobile device of a user or to a receiving unit integrated in the hydrofoil watercraft. The loudspeaker may be used for emitting sounds such as music and/or instructions from a navigation system.

According to an aspect, a remote control may be provided which is configured to provide navigation functions. The remote control may comprise the features as already mentioned before with respect to other aspects and embodiments. In addition or alternatively, the remote control may comprise a display 27. The display may show a map and/or navigation information. Navigation information may be entered (uploaded) into the remote control or a navigation unit in the board assembly wirelessly coupled to the remote control. The remote control may further comprise an emergency button 28.

In conclusion, it is pointed out that the terms like “comprising” or the like are not intended to rule out the provision of additional elements or steps. Let it further be noted that “a” or “an” do not preclude a plurality. In addition, features described in conjunction with the different embodiments can be combined with each other however desired. It is also noted that the reference numbers in the claims are not to be construed as limiting the scope of the claims. Moreover, while at least one exemplary embodiment has been presented in the foregoing summary and detailed description, it should be appreciated that a vast number of variations exist.

It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration in any way. Rather, the foregoing summary and detailed description will provide those skilled in the art with a convenient roadmap for implementing an exemplary embodiment, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope as set forth in the appended claims and their legal equivalents.

REFERENCE SIGNS

-   -   1 Hydrofoil watercraft 162 Inlet section     -   10 Board assembly 163 Intermediate section     -   11 Hull 164 Outlet section     -   12 Lower portion 170 Outer housing portion     -   13 Upper portion 171 Propulsion device accommodating     -   14 Support surface section     -   15 Access panel 172 Nozzle section     -   16 Control unit 173 Inner surface section     -   17 First wireless receiving unit 174 Stator/Stator portion     -   18 Second wireless receiving unit 175 Guide vane     -   19 Humidity sensor 176 Outer circumferential portion     -   20 Accumulator 177 Upstream end portion     -   21 Remote control 178 Inlet opening     -   22 Measurement device 179 Downstream end portion     -   23 Heart rate detection means 180 Inner housing portion     -   24 Temperature detection means 181 Outer surface section     -   25 Motion sensor 182 Front end portion     -   26 Heating portion 183 Rear end portion     -   27 Display 184 Inlet angle     -   28 Emergency button 190 Strut     -   30 Mast assembly 191 Outlet opening     -   51 End portion 192 Outlet opening varying device     -   52 Board assembly fixation portion 193 Flexible elongate members     -   53 End portion 194 Manipulating device     -   54 Fuselage assembly fixation portion 195 Nozzle section     -   55 Middle section 196 Flaps     -   56 Electric line 197 Signal/Energy transmission     -   100 Fuselage assembly arrangement     -   101 Front portion 198 Transceiver     -   102 Front section 199 Transceiver     -   103 Middle section 200 Propulsion device     -   104 Rear section 201 Impeller     -   105 Wing attachment section 202 Rear bearing     -   106 Mast assembly fixation section 203 Drive shaft     -   107 Mounting recess 204 Front bearing     -   108 Coupling section 205 Electric motor     -   109 Accommodating section 206 Humidity sensor     -   110 Casing 207 Controller     -   111 Opening 300 Tail unit     -   112 Front wing 301 Stabilizing member     -   140 Rear portion 302 Wing     -   141 Coupling section 310 Attachment portion     -   142 Coupling flange 311 Attachment flange     -   143 Cylindrical portion 312 Supporting surface     -   144 Outer circumferential surface 313 Threaded opening     -   145 Engaging portion/threaded opening 314 Threaded fastener     -   146 Accommodating section 400 Drive device     -   147 Accommodating space 401 Inlet opening     -   148 Fixation flange 402 Outlet opening     -   149 Fixation openings 500 Hydrofoil assembly     -   150 fastening member/screw 501 Fuselage     -   160 Propulsion section 502 Front wing     -   161 Flow channel 510 Tail unit     -   511 Stabilizing member 702 User detection device     -   512 Wing 703 Water depth determining device     -   600 Cooling arrangement 704 Display     -   601 Piping system 705 Lighting portion     -   602 Inlet opening 706 Heating portion     -   603 Outlet opening 707 Loudspeaker     -   604 Heat exchanger A1 Longitudinal middle axis     -   700 Communication means     -   701 Transceiver 

1. A fuselage assembly (100) configured to be attached to a mast assembly (50) of a powered hydrofoil watercraft (1), wherein said fuselage assembly (100) comprises a mast assembly fixation section (106) and an outer housing portion (170) which accommodates a propulsion device (200), and which outer housing portion (170) at least partially limits an outer dimension of a flow channel (161) through which water is transported during operation of said hydrofoil watercraft (1), wherein said flow channel (161) is formed such that its cross sectional area is reduced towards an outlet side of said flow channel (161), and wherein (I) said outer housing portion (170) comprises an attachment portion (310) on which a tail unit (300), is formed or attachable thereto and/or wherein (II) said propulsion device (200) is accommodated in said outer housing portion (170) such that a user is prevented from touching said propulsion device (200).
 2. The fuselage assembly (100) according to claim 1, wherein said outer housing portion (170) is configured for detachably fixing said tail unit (300) to the same, or wherein alternatively said outer housing portion (170) and said tail unit (300) are integrally formed.
 3. The fuselage assembly (100) according to claim 1, further comprising a wing attachment section (105) and a front wing (112) attached to said wing attachment section (105), wherein said wing attachment section (105) is provided at a front portion (101) of said fuselage assembly (100) and is configured to detachably mount said front wing (112).
 4. The fuselage assembly (100) according to claim 3, wherein said tail unit (300) and/or said front wing (112) mounted on said fuselage assembly (100) are configured to be transferable between a use state in which said tail unit (300) is able to exert a stabilizing function and/or said front wing (112) is positioned to generate a lifting force, and a stowing state, wherein in said stowing state a mast assembly profile and a profile of said tail unit (300) and/or of said front wing (112) are arranged substantially in one plane, wherein said tail unit (300) and/or said front wing (112) are rotatable about a rotational axis, for example a longitudinal middle axis (A1) of said fuselage assembly (110) or an axis parallel to said longitudinal middle axis (A1), such that said tail unit (300) and/or said front wing (112) are rotatable about 90° between said use state and said stowing state.
 5. The fuselage assembly (100) according to claim 1, wherein said outer housing portion (170) comprises an upstream end portion (177) defining an inlet opening (178) and wherein said housing portion (170) comprises a downstream end portion (179) which comprises a nozzle section (172) with an outlet opening (191), wherein a cross sectional area of said inlet opening (178) is larger than a cross sectional area of said outlet opening (191), wherein said cross sectional area at said outlet opening (191) is at least 5% smaller than said cross sectional opening of said inlet opening (178) and wherein said cross sectional area at said outlet opening (191) is 90% to 80% the size of said cross sectional area of said inlet opening (178), wherein in addition or alternatively said nozzle section (172) is detachably configured and is made from a plastics material.
 6. The fuselage assembly (100) according to claim 5, wherein said outer housing portion (170) and said propulsion device (200) accommodated therein are configured and arranged with respect to each other such that it is not possible to reach said propulsion device (200) with a human extremity, wherein a length of said outer housing portion (170) and/or the size of said inlet opening (178) and/or the size of said outlet opening (191) and/or the position of said propulsion device (200) in said outer housing portion (170) and/or a dimension of said flow channel (161) are adjusted and/or positioned such that said propulsion device (200) cannot be reached by means of a human extremity through said inlet opening (178) and said outlet opening (191) and/or wherein a safety member is provided which blocks an access for human extremities, wherein said safety member is provided downstream or upstream of said propulsion device (200) and is a stator (174), and wherein in addition or alternatively said length of said flow channel (161) between said inlet opening (178) and said propulsion device (200) is at least 30 mm and/or wherein in addition or alternatively a height or width of said inlet opening (178) is equal to or smaller than 30 mm, and/or wherein in addition or alternatively a length of said stator (174) in flow direction of said flow channel (161) is equal to or larger than 5 mm and/or wherein in addition or alternatively said size of said outlet opening is equal to or smaller than 30 mm.
 7. The fuselage assembly (100) according to claim 5, wherein said flow channel (161) is formed between said outer housing portion (170) and an inner housing portion (180) which is suitable for supporting said propulsion device (200), and/or wherein said flow channel (161) is formed as a ring channel extending about said longitudinal middle axis (A1) and circumferentially surrounding said inner housing portion (180) with its cross section in a direction perpendicular to said longitudinal middle axis (A1) defining a ring and/or wherein said inlet opening (178) is formed between said upstream end portion (177) and an outer surface section (181) of said inner housing portion (180), and/or wherein said inlet opening (178) is formed as an annular inlet opening or an elliptical inlet opening, and/or wherein said flow channel (161) is configured such that an inlet angle (184) smaller than 20° is realized at said inlet opening (178).
 8. The fuselage assembly (100) according to claim 5, wherein said outer housing portion (170) is connected to said inner housing portion (180) via circumferentially distributed struts (190) arranged around said longitudinal middle axis (A1) so that said outer housing portion (170) is held cantilevered on said inner housing portion (180), said struts (190) at least partially extending in the longitudinal direction of said fuselage assembly (110) and bridging said inlet opening (178), wherein said struts (190) are aerodynamically formed so as to reduce turbulences and comprise a wing shape.
 9. The fuselage assembly (100) according to claim 8, wherein at least a portion of said outer housing portion (170), and said rear end portion (183) of said inner housing portion (180) are fixedly coupled to each other, thereby defining a propulsion section (160) of said fuselage assembly (100), and wherein in addition or alternatively said propulsion section (160) is detachably coupled to a front portion (101) of said fuselage assembly (100).
 10. The fuselage assembly (100) according to claim 5, further comprising a flap mechanism for selectively opening and closing said inlet opening (178), wherein said flap mechanism is designed such that a negative pressure generated by said propulsion device (200) automatically actuates said flap mechanism, wherein said flap mechanism comprises one or more flaps which are pre-biased in the closing direction, and which flaps are moved into an opened position against the pre-biasing force when there is a corresponding negative pressure and are automatically moved into a closed position driven by the pre-biasing force when there is no sufficiently large negative pressure.
 11. The fuselage assembly (100) according to claim 1, further comprising a front portion (101) adapted to sealingly receive an electric motor, wherein said electric motor is thermally coupled to a casing (110) of said front portion (101) for cooling purposes, wherein optionally a motor housing of said electric motor also forms a part of said casing (110) of said front portion (101) in such a manner that said motor housing gets in contact with water on its outer side, such that a direct cooling of said electric motor is possible.
 12. The fuselage assembly (100) according to claim 11, wherein said front portion (101) is further adapted to receive a controller couplable to said electric motor, said controller being thermally coupled to said casing (110) of said front portion (101) for cooling purposes, wherein said front portion (101) optionally comprises a controller receiving space separated and sealed from an electric motor receiving space.
 13. The fuselage assembly (100) according to claim 1, wherein said mast assembly fixation section (106) bels provided on a top side of said fuselage assembly (110), wherein in addition or alternatively said mast assembly fixation section (106) comprises a mounting recess (107) in which a fuselage assembly fixation portion (54) of said mast assembly (50) can be inserted and locked, wherein said mast assembly fixation section (106) is designed for a positive locking or an integral connection of said mast assembly (50) with said mast assembly fixation section (106).
 14. An integrated propulsion unit for a powered hydrofoil watercraft, comprising the fuselage assembly (100) according to claim 1, an electric motor provided in said fuselage assembly (110) and a propulsion device (200) provided in said outer housing portion (170), said electric motor being operatively connected to said propulsion device (200) by means of a drive shaft (203) accommodated in said inner housing portion (180), or wherein said propulsion device (200) is directly coupled to an output shaft of said electric motor.
 15. A hydrofoil watercraft (1), comprising a board assembly (10), a mast assembly (50) coupled to a lower portion (12) of said board assembly (10), and the integrated propulsion unit according to claim 14, wherein a front wing (112) and the tail unit (300) are attached to said fuselage assembly (100) of said integrated propulsion unit.
 16. The fuselage assembly of claim 2, wherein said detachable fixation is achieved by means of positive locking, and wherein said outer housing portion (170) comprises an attachment portion (310) for detachably attaching said tail unit (300).
 17. The fuselage assembly of claim 16, wherein the positive locking is a latching plug and socket connection having a dovetail geometry or being realized by pins.
 18. The fuselage assembly of claim 16, wherein the tail unit comprises an attachment flange having a threaded opening.
 19. The fuselage assembly of claim 4, wherein said wing attachment section (105) and/or said attachment portion (310) are individually rotatable about said rotational axis or wherein said mast assembly fixation section (106) is configured such that said fuselage assembly is rotatably coupled to said mast assembly (50).
 20. The fuselage assembly of claim 1, wherein the tail unit a stabilizing member (301) optionally wherein the stabilizing member is a stabilizing wing (302). 